Atom is the smallest matter in ther world. The situation above is not likely to happen because you cannot divide or split an atom in half.
In a chemical reaction, no atoms change its form, but they change the way they are grouped together.
Here's the brief history of the structure of atom....
ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡+｡･ﾟ･｡
In 460 BC, Greek philosopher Democritus came up with the idea of atoms. He thought that the matter is composed of smallest possible particles. For more than 2000 years after Democritus, noother scientists did anything to develop his theory until people started to question the structure of matter again.
In 1897, the English physicist J.J Thompson came up with his "Plum pudding model".
He also discovered that the atom is composed of much smaller particles; Electrons with negative charge and He thought that the rest of atom had positive charge.
In eary 20th centry, Physicists such as Max Planck and Albert Einstein expanded the idea of "quanta". They suggested that the energy can only be mesured in discrete units called quanta and that the quanta. Also, Photoelectric effect, that the atoms do not only emit photons ( discrete light particle) but they can also absorb them, was introduced by Planck and proved by Einstein.
Based on his experiments using alpha rays, Rutherfold came up with his new version of atomic model, that consisted of nucleus and the electrons surrounding it.
Finally, In 1912, Danish physicist Niels Bohr came up with two rules on the structure of atoms.
Rule 1. Electrons can orbit at certain allowed distances from the nucleus
Rule 2. Atoms radiate energy when an electron jumps from one orbit to another orbit with lower energy and ansorb energy when an electron gets boosted from one orbit to another with higher energy.
Based on his rules, Bohr was able to construct a diagram of atom which is still used today.
☆･｡ﾟ･｡･oﾟ･｡ﾟ･｡･oﾟ☆･｡ﾟ･｡･oﾟ･｡ﾟ･｡･oﾟ☆･｡ﾟ･｡･oﾟ･｡ﾟ･｡･oﾟ☆☆･｡ﾟ･｡･oﾟ･｡ﾟ･｡･oﾟ☆･｡ﾟ･｡･oﾟ･｡ﾟ･｡･oﾟ☆･｡ﾟ･｡･oﾟ･｡ﾟ･｡･oﾟ☆
Atomic Structure
Atom is composed of three smaller particles: Protons, Neutrons, and Electrons
The table above shows the characteristics of each particle. As shown on the left, the electron is sorrounding the nucleus, that is composed of protons and neutrons. 
There are three atomic species.......
Neutral Atom is the atom with no net charge.
In this type of atom, Atomic Number = Number of Protons = Number of Electrons.
For example, Gold (Au) has an atomic number of 79, which means it has 79 protons and 79 neutrons.
Ion is the atom that is capable of gaining or losing electrons.
Negative charged ion (aka. anion) is an ion that gains electrons. Non-metals are the anions.
Positive charged ion (aka. cation ) is an ion that loses electrons. Metals are the cations.
In this case, number of protons can be calculated by Protons - Charge.
Isotopes are the atomic species that have same atomic number / number of protons but different atomic masses / mass numbers.
In all species, the number of neutrons are calculated by Atomic mass - Number of Protons.
BUT..... WHAT HAPPENS IF YOU ADD (OR SUBTRACT) PROTONS, ELECTRONS, OR NEUTRONS TO THE ATOM?????
If Protons are added....new element will be produced!!!!
EX. If you add two protons to the calcium (with 20 protons,) the number of protons of the calcium will be 22......which means it is not calcium anymore, but it is now Titanium!!!
If Electrons are added....the ion is formed!!!
Ex. If you add three electrons to Phosphorus (with 15 electrons,) the number of electrons of Phosphorus will be 18.....which means it is now the positively charged ion!!!
If Neutrons are added....the heavier version of the same element (isotope) is formed!!!
EX. If you add 5 neutrons to indium (with atomic mass of 115,) the atomic mass will become 116 since the neutron has a mass of 1....which means it is heavier!!!
You Can Calculate the Average Atomic Mass by adding given parcentage of each isotopes;
Example: 20% of 58g Nickel, 12% of 59 Nickel, and 68% of 60 Nickel is obained.
The average atomic mass of Nickel is.....
(0.20x58)+(0.12x59)+(0.68x60)=59.48 = 59g
No comments:
Post a Comment